Electrostatic precipitator



April 18, 1950 L. LINCOLN 2,504,430

ELECTROSTATIC PRECIPITATOR Filed Jan. 51, 1947 2 Sheet-Sheet 1 a as I VEN TOR. 26 f;

Fo/and L). Luisa/n BY \l: L. LINCOLN ELECTR STATIC PRECIPITATOR 4 aIJIILL A rilis, 1950 Filed Jan. 51, 1947 Patented Apr. 18, 195 0 UNITEDSTATES ATENT OFFICE ELECTROSTATIC PRECIPITATOR Application January 31,1947, Serial No. 725,487

2 Claims. 1

This invention relates to electrostatic precipitators for the removal offoreign particles such as dust, from gases, such as air.

The most successful electrostatic precipitators for the removal of dustand other small foreign particles from gases, utilize ionizing chambershaving oppositely charged, ionizer electrodes casing by 12,000 voltinsulators, and the charged collector electrodes areusually insulatedfrom the grounded casing by 6,000 volt insulators. The 12,000 voltinsulators are not only much more expensive than the 6,000 voltinsulators, but they are much larger and extend greater distances intothe gas stream passing through the precipitator.

This invention eliminates the necessity for the higher voltageinsulators usually provided for supporting the ionizer wire electrodesof an electrostatic precipitator from the casing thereof, by supportingthe charged collector electrodes from the casing by relatively lowvoltage insulators, and by supporting the ionizer wire electrodes byrelatively low voltage insulators from charged collector electrodes.Thus 6,000 volt insulators may be used to support charged collectorelectrodes from a casing, and 6,000 volt insulators may be used forsupportin ionizer wire electrodes from charged collector electrodes.

Objects of the invention are to simplify the construction of, and toreduce the manufacturing cost of, electrostatic precipitators.

The invention will now be described with reference to the drawing, ofwhich:

Fig. 1 is a side elevation, in section, of an electrostatic precipitatorembodying this invention;

Fig. 2 is a sectional view along the lines 2-2 of Fig. 1, and

Fig. 3 is a sectional view along the lines 33 of Fig.2.

The electrostatic precip'itator illustrated has the sheet metal casingl0 which is adapted to be grounded as is usual in such devices. Thegrounded collector electrodes ll formed in the illustrated embodiment ofthe invention, as metal plates, are supported from the casing it by thecylindrical, metal rods l2 which extend through apertures therein. Thecylindrical, metal spacers l3 extend around the rods I 2 between theadjacent electrodes H and between the outer electrodes H and theadjacent Walls of the casing, and serve to space the electrodes ll apartin parallel relationship, and to provide good electric contact betweenthe electrodes H and the rods, the spacers fitting tightly around therods, and contacting substantial surfaces of the electrodes H. The endsof the rods i2 extend through the casing walls, and are threaded toreceive the nuts M, which when screwed up on the threaded ends of therods, tighten the described electrode supports to the casing.

The two, outer charged electrodes l5, illustrated as metal plates, aresupported from the casing H! by the electric insulators it which haverelatively large diameters, and relatively small thicknesses. The inner,charged electrodes 18, are supported from the outer, charged electrodesl5 by the cylindrical, metal rods H which extend through aperturestherein parallel to the rods I2. The cylindrical, metal spacers isextend around the rods l7 between the adjacent electrodes l8 and betweenthe outer electrodes [8 and the electrodes I5, and serve to space thecharged electrodes apart in parallel relationship, and to provide goodelectric contact between same and the rods ll, the spacers l9 fittingtightly around the rods ll, and contacting substantial surfaces of thecharged electrodes.

The outer ends of the rods ll are threaded where they extend through theelectrodes l5, for receiving the nuts 24 which secure the describedcharged electrode assembly in position, when screwed up on the threadedrod ends against the outer surfaces of the electrodes it.

The rods I2 and the spacers l3 therearound pass through the clearanceholes 20 in the charged electrodes 15 and E8, the clearance holes beingsufiiciently large that there is no electrical leakage between thecharged electrodes and the spacers.

The rods l! and the spacers l9 therearound pass through the clearanceholes 2! in the grounded electrodes I l, the clearance holes beingsufficiently large that there can be no electrical leakage between thegrounded electrodes and the spacers IS.

The casing in has a gas inlet grille 25 in its upper portion, andextending between same and the described collector electrodes, are thetubular ionizer electrodes 26, which contact the end walls of the casingso as to be grounded thereto, and which extend with their axes parallelto the rods l2 and IT.

The upper ends of the charged electrodes [5 extend into the spacebetween the tubular electrodes 26 and the upper ends of the electrodes Hand Land have attached to their inner sides by the bolts 28, theinsulators 29 which preferably are similar to the insulators l6described in the foregoing. The inner sides of the insulators 29 haveattached thereto by the --bolts 30, the metal framework 3l to which areattached the ionizer wires 32 which are equally spaced between thetubular, ionizer electrodes 720, and which extend parallel thereto.

In the embodiment of the invention illustrated, the casing l0, thecollector electrodes II and the tubular, ionizer electrodes '26 aregrounded as described, and are adapted to be connected to the negativeterminal "ofa sui'table direct current power supply, the rods l-Z andthe spacers l3 ther'earoundin contact with the electrodes ll providinggood electrical connections between the electrodes H and the'c'asing.The charged electrodes l5 may be connected to the +6,000 volt terminalof the power supply. The ionizer wires 32 may be connected through theframework ill to the +l2,000 volt terminal of the power supply.

The ionizer wires 32 are seen to be insulated from the casing ill by theinsulators i6 and-'29 connected electrically in series. Thus instead ofrequiring as in the usual construction, a set of 6,000 volt insulatorsfor insulating the charged collector electrodes from the casing, and aset of 12,000 volt insulators for insulating the ionizer wire electrodesfrom the casing, two sets of the lower voltage insulators may be used.The cost of the lower voltage insulators is less'than that of the highervoltage ones, and they occupy less space, and provid less obstruction togas 'flow.

The operation of the electrostatic precipitator is similar to that ofthe conventional ones which are well known to those skilled in the art,in that the gas entering the inlet 25 under the influence of an externalfan, is ionized on passage between the ionizer wires '32 and thetubular, ionizer electrodes 26, whereby the dust and other irigadiiacntparallel opposite walls of said cas- "in'g, insulatorsbetween the outersides of said plates and -'said walls for supporting said plates:therefrom, other charged collector plates supported from said plates,said pair of plates having corresponding ends extending beyond saidother plates, ionizer wireelectrodes in'said easing, and means includinginsulators-attached to the inner sides of said ends for supporting saidwire-electrodes therefrom.

2. An electrostatic precipitator comprising-a casing, a pairof "chargedcollector plates extend ing adjacent parallel opposite walls 'of saidcasin'g, insulators between the outer sides of said plates and saidwalls -fo'r supporting said plates therefrom, tubular ionizer electrodesattached to said walls, other charged collector plates supported fromsaid pair of plates, said pair 'of plates having corresponding endsextendin'g'beyondsaid other plates towards said tubular electrodes butterminating-short thereof, ionizer wire electrodes between said tubularelectrodes, insulators attached to the inner sides of said ends, andwire electrode supporting means attached to said last mentionedinsulators.

ROLAND In; LINCOLN.

REFERENCES CITED The following references are of record in the me 'ofthis patent:

UNITED STATES PATENTS Number Name Date 1 2,142,129 Bos et al; Jan. 3,1939 2,255,677 Penney Sept. 9,- 1941

